X-ray imaging apparatus and method for controlling the same

ABSTRACT

An X-ray imaging apparatus includes an imaging device that captures a camera image of a target, a controller that stitches a plurality of X-ray images of a plurality of divided regions to generate one X-ray image of the target, and a display that displays a settings window providing a graphical user interface for receiving a setting of an X-ray irradiation condition for the divided regions, and displays the camera image in which positions of the divided regions are displayed.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application claims priority from Korean Patent Application Nos.10-2015-0119878, 10-2015-0120581, and 10-2016-0108198 filed Aug. 25,2015, Aug. 26, 2015, and Aug. 25, 2016, respectively, in the KoreanIntellectual Property Office. The disclosures of all of the aboveapplications are incorporated herein by reference in their entireties.

BACKGROUND

1. Field

Methods and apparatuses consistent with exemplary embodiments relate toan X-ray imaging apparatus in which a portion of an object to be imagedis divided into regions, the regions are imaged, and then the imagedregions are stitched, and a method for controlling the same.

2. Description of the Related Art

An X-ray imaging apparatus irradiates an object with X-rays and analyzesX-rays that have been transmitted through the object to recognize aninner structure of the object. Since X-ray transmittance variesaccording to a tissue forming an object, an inner structure of theobject may be imaged using an attenuation coefficient which is anumerical value of X-ray transmittance.

A part which is desired to be imaged may not be entirely captured by asingle imaging in some cases due to various reasons including a case inwhich the impinging X-ray irradiation beam is smaller than a portion tobe imaged and a case in which a detector region is smaller than aportion to be imaged.

Accordingly, one X-ray image of the desired portion to be imaged may beobtained by capturing partial X-ray images and combining the partialX-ray images.

SUMMARY

One or more exemplary embodiments provide an X-ray imaging apparatusthat displays a plurality of divided regions, with which stitchingimaging will be performed on a camera image, and has the divided regionsdisplayed on the camera image interoperate with an X-ray irradiationcondition setting screen for each of the divided regions to allow a userto intuitively and easily recognize the divided region for which anX-ray irradiation condition is being set, and a method for controllingthe same.

Additional aspects of the disclosure will be set forth in part in thedescription which follows and, in part, will be obvious from thedescription or may be learned by practice of the disclosure.

According to an aspect of an exemplary embodiment, an X-ray imagingapparatus includes an imaging device that captures a camera image, acontroller that stitches a plurality of X-ray images of a plurality ofdivided regions to generate one X-ray image, and a display that displaysa settings window providing a graphical user interface for receiving asetting of an X-ray irradiation condition for each of the plurality ofdivided regions and the camera image in which positions of the pluralityof divided regions are displayed.

The display may display a plurality of divided windows showing thepositions of the plurality of divided regions by overlaying theplurality of divided windows on the camera image.

The display may have the settings window and the camera image on whichthe plurality of divided windows are overlaid interoperate anddisplayed.

When one of the plurality of divided regions is selected, the displaymay activate the graphical user interface for receiving a setting of anX-ray irradiation condition of the selected divided region to displaythe graphical user interface on the settings window and may display aposition of the selected divided region on the camera image.

The display may display a plurality of identification tags respectivelycorresponding to the plurality of divided regions on the settings windowand, when one of the plurality of identification tags is selected, mayactivate a graphical user interface for receiving a setting of an X-rayirradiation condition of a divided region corresponding to the selectedidentification tag.

The display may display a position of the divided region correspondingto the selected identification tag on the camera image.

When one divided window among the plurality of divided windows displayedin the camera image is selected, the display may activate a graphicaluser interface for receiving a setting of an X-ray irradiation conditionof a divided region corresponding to the selected divided window.

The display may display a graphical object for receiving the setting ofthe X-ray irradiation condition by overlaying the graphical object onthe camera image.

The display may display the graphical user interface on the settingswindow by synchronizing the graphical user interface with a commandinput through the graphical object displayed in the camera image.

The display may display the graphical object for each of the pluralityof divided regions.

The display may display identification tags respectively matching theplurality of identification tags displayed on the settings window on theplurality of divided windows.

The display may display at least one of the maximum height from groundand the minimum height from ground of the plurality of divided regionson the camera image.

The display may display a size of a collimation region applied to atleast one of the plurality of divided regions on a corresponding dividedwindow.

The display may display a top line showing the top of a stitching regionincluding the plurality of divided regions and a bottom line showing thebottom of the stitching region on the camera image.

The display may display the top line and the bottom line at a positioncorresponding to a selected protocol.

The display may display the bottom line at a lower end portion of thecamera image.

According to an aspect of an exemplary embodiment, an X-ray imagingapparatus includes an X-ray source that radiates X-rays, a collimatorthat performs collimation of the radiated X-rays, an imaging device thatcaptures a camera image, and a display that displays the camera imageand overlays and displays at least one of a size displaying graphicalobject showing a size of a collimation region, a length displayinggraphical object showing a length of an object, and a distancedisplaying graphical object showing a distance between the X-ray sourceand the object or a distance between the X-ray source and an X-raydetector on the camera image.

The display may display an irradiation window corresponding to thecollimation region by overlaying the irradiation window on the cameraimage.

The display may display a size displaying graphical object showing awidth of the collimation region at an upper portion of the irradiationwindow and may display a size displaying graphical object showing aheight of the collimation region at a side portion of the irradiationwindow.

The X-ray imaging apparatus may further include a controller that, whena size of the irradiation window is adjusted, controls the collimator toallow the adjusted size of the irradiation window to correspond to thesize of the collimation region.

When an identical X-ray imaging is performed again, the display maydisplay together an irradiation window that has been applied to previousX-ray imaging and an irradiation window to be applied to current X-rayimaging.

The length displaying graphical object may be displayed in a form of atool that measures a length using a plurality of scales.

The length displaying graphical object may show an absolute length of anobject shown in the camera image.

The display may display a top line for designating an upper boundary ofa region in which X-ray imaging will be performed and a bottom line fordesignating a lower boundary thereof on the camera image and, when anidentical X-ray imaging is performed again, may display a top line and abottom line that has been applied to previous X-ray imaging and a topline and a bottom line to be applied to current X-ray imaging together.

According to an aspect of an exemplary embodiment, a method forcontrolling an X-ray imaging apparatus includes capturing a cameraimage, receiving a selection related to a stitching region including aplurality of divided regions by the camera image, and displaying asettings window providing a graphical user interface for receiving asetting of an X-ray irradiation condition for each of the plurality ofdivided regions and the camera image in which positions of the pluralityof divided regions are displayed.

The displaying may include displaying a plurality of divided windowsshowing positions of the plurality of divided regions by overlaying theplurality of divided windows on the camera image.

The displaying may further include displaying a plurality ofidentification tags respectively corresponding to the plurality ofdivided regions in the settings window and, when at least one of theplurality of identification tags is selected, activating a userinterface of a divided region corresponding to the selectedidentification tag.

The displaying may further include displaying a position of the dividedregion corresponding to the selected identification tag on the cameraimage.

The displaying may further include, when at least one divided windowamong the plurality of divided windows displayed in the camera image isselected, activating a graphical user interface for receiving a settingof an X-ray irradiation condition of a divided region corresponding tothe selected divided window.

The displaying may further include displaying a graphical object forreceiving the setting of the X-ray irradiation condition by overlayingthe graphical object on the camera image.

The displaying may further include displaying the graphical userinterface in the settings window by synchronizing the graphical userinterface with a command input through a graphical object displayed inthe camera image.

The displaying may further include displaying at least one of themaximum height from ground and the minimum height from ground of theplurality of divided regions in the camera image.

According to an aspect of an exemplary embodiment, a method forcontrolling an X-ray imaging apparatus includes capturing a cameraimage, displaying the camera image, and overlaying and displaying atleast one of a size displaying graphical object showing a size of acollimation region, a length displaying graphical object showing alength of an object, and a distance displaying graphical object showinga distance between an X-ray source and the object or a distance betweenthe X-ray source and an X-ray detector on the camera image.

The displaying may further include displaying an irradiation windowcorresponding to the collimation region by overlaying the irradiationwindow on the camera image.

The displaying may further include displaying a size displayinggraphical object showing a width of the collimation region at an upperportion of the irradiation window and displaying a size displayinggraphical object showing a height of the collimation region at a sideportion of the irradiation window.

The method may further include, when a size of the irradiation window isadjusted, controlling a collimator to allow the adjusted size of theirradiation window to correspond to the size of the collimation region.

The method may further include, when an identical X-ray imaging isperformed again, displaying an irradiation window that has been appliedto previous X-ray imaging and an irradiation window to be applied tocurrent X-ray imaging together.

The length displaying graphical object may be displayed in a form of atool that measures a length using a plurality of scales and show anabsolute length of an object shown in the camera image.

The method may further include displaying a top line for designating anupper boundary of a region in which X-ray imaging will be performed anda bottom line for designating a lower boundary thereof on the cameraimage and, when an identical X-ray imaging is performed again,displaying a top line and a bottom line that has been applied toprevious X-ray imaging and a top line and a bottom line to be applied tocurrent X-ray imaging together.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects will become more apparent by describingcertain exemplary embodiments with reference to the accompanyingdrawings, in which:

FIG. 1 is a control block diagram of an X-ray imaging apparatusaccording to an exemplary embodiment;

FIG. 2A is an exterior view illustrating a configuration of the X-rayimaging apparatus according to an exemplary embodiment;

FIG. 2B is an exterior view illustrating a sub-display device mounted onan X-ray source according to an exemplary embodiment;

FIG. 3A is a view illustrating a configuration of a collimator includedin an X-ray source according to an exemplary embodiment;

FIG. 3B is a lateral cross-sectional view of a blade taken along lineA-A′ in FIG. 3A;

FIG. 4 shows an X-ray source viewed from the front;

FIGS. 5A and 5B are views each illustrating an example of an automaticexposure control (AEC) sensor that may be used in the X-ray imagingapparatus according to an exemplary embodiment;

FIGS. 6, 7, 8, and 10 are views each illustrating an example of a screendisplayed on a display according to an exemplary embodiment;

FIGS. 11A, 11B, and 11C are views for describing an example of a methodfor measuring a distance between an X-ray detector and an X-ray sourceaccording to an exemplary embodiment;

FIG. 12A is a view illustrating an example of a stitched-together image;

FIG. 12B is a view illustrating an example in which an imaging region isdivided to perform stitching imaging;

FIG. 12C is a view illustrating overlapping regions between each of aplurality of divided regions;

FIGS. 12D and 12E are views illustrating an operation in whichoverlapping regions are automatically adjusted

FIGS. 13 and 14 are views illustrating an example of a screen displayedfor receiving a designation related to a region in which stitchingimaging will be performed according to an exemplary embodiment;

FIG. 15 is a view illustrating an example of a screen providinginformation on a height of a stitching region according to an exemplaryembodiment;

FIGS. 16A and 16B are views illustrating a screen that allows a user toset an X-ray irradiation condition according to an exemplary embodiment;

FIGS. 17, 18, and 19 are views illustrating a screen that allows a userto set an X-ray irradiation condition according to an exemplaryembodiment;

FIGS. 20, 21, 22, and 23 are views illustrating an example of agraphical user interface that allows making a selection of an X-rayirradiation condition according to an exemplary embodiment;

FIGS. 24 and 25 are views illustrating a screen that allows a user toselect an AEC sensor in the X-ray imaging apparatus according to anexemplary embodiment;

FIGS. 26A, 26B, and 26C are views related to stitching imaging accordingto an exemplary embodiment;

FIG. 27 is a flowchart of a method for controlling an X-ray imagingapparatus according to an exemplary embodiment;

FIG. 28 is a flowchart of an example of performing the method forcontrolling an X-ray imaging apparatus according to an exemplaryembodiment; and

FIG. 29 is a flowchart illustrating an example of performing stitchingimaging according to an exemplary embodiment.

DETAILED DESCRIPTION

Exemplary embodiments are described in greater detail below withreference to the accompanying drawings.

In the following description, like drawing reference numerals are usedfor like elements, even in different drawings. The matters defined inthe description, such as detailed construction and elements, areprovided to assist in a comprehensive understanding of the exemplaryembodiments. However, it is apparent that the exemplary embodiments canbe practiced without those specifically defined matters. Also,well-known functions or constructions are not described in detail sincethey would obscure the description with unnecessary detail.

FIG. 1 is a control block diagram of an X-ray imaging apparatusaccording to an exemplary embodiment, FIG. 2A is an exterior viewillustrating a configuration of the X-ray imaging apparatus according toan exemplary embodiment, and FIG. 2B is an exterior view illustrating asub-display device mounted on an X-ray source. An exterior illustratedin FIG. 2A is an example of an X-ray imaging apparatus and relates to aceiling type X-ray imaging apparatus in which an X-ray source isconnected to a ceiling of an examination room.

Referring to FIG. 1, an X-ray imaging apparatus 100 according to anexemplary embodiment includes an X-ray source 110 that generates andradiates X-rays, an imaging device 120 that captures a camera image, adisplay 150 that displays the camera image captured by the imagingdevice 120, a screen through which an X-ray irradiation condition may beset, etc., an input unit 160 that receives control commands including acommand for setting an X-ray irradiation condition from a user, astorage unit 170 that stores information related to an X-ray irradiationcondition, and the like, and a controller 140 that controls an overalloperation of the X-ray imaging apparatus 100.

For example, the X-ray imaging apparatus 100 may further include acommunication unit 130 that communicates with an external device.

The controller 140 may control a time point at which X-rays are radiatedfrom the X-ray source 110, an X-ray irradiation condition, etc.according to a command input by the user and may generate an X-ray imageusing data received from an X-ray detector 200.

For example, the controller 140 may also control a position or anorientation of mounting units 14 and 24 on which the X-ray detector 200is mounted according to an imaging protocol and positions of an object1.

The controller 140 may include a memory in which a program forperforming the operations described above and operations to be describedbelow is stored and a processor that executes the stored program. Thecontroller 140 may include one processor or one microprocessor or aplurality of processors or microprocessors. In the latter case, theplurality of processors or microprocessors may be integrated in one chipor may be physically separated from each other.

When the controller 140 includes a plurality of processors and aplurality of memories, some of the memories and the processors may beprovided at a work station 180 (see FIG. 2A) and the remaining memoriesand processors may be provided in other devices such as a sub-displaydevice 80 (see FIG. 2A) or a moving carriage 40 (see FIG. 2A). Forexample, a processor provided in the work station 180 may performcontrolling of image processing and the like for generating an X-rayimage, and a processor provided in the sub-display device or the movingcarriage may perform controlling related to a movement of the X-raysource 110 or the X-ray detector 200.

The X-ray imaging apparatus 100 may be connected to an external device(e.g., an external server 310, a medical apparatus 320, and/or aportable terminal 330 such as a smartphone, a tablet personal computer(PC), and/or a wearable device) via the communication unit 130 andtransmit or receive data.

The communication unit 130 may include one or more elements that enablecommunicating with an external device. For example, the communicationunit 130 may include at least one of a short-distance communicationmodule, a wired communication module, and a wireless communicationmodule. For example, the communication unit 130 may further include aninner communication module that enables communication between elementsof the X-ray imaging apparatus 100.

For example, the communication unit 130 may receive a control signalfrom an external device and transmit the received control signal to thecontroller 140 to allow the controller 140 to control the X-ray imagingapparatus 100 according to the received control signal.

For example, the controller 140 may also control an external deviceaccording to the control signal from the controller 140 by transmittingthe control signal to the external device via the communication unit130. For example, the external device may process data of the externaldevice according to the control signal from the controller 140 receivedvia the communication unit 130. Since a program capable of controllingthe X-ray imaging apparatus 100 may be installed in the external device,the program may include an instruction that executes some or alloperations of the controller 140.

The program may be pre-installed in the portable terminal 330, and theprogram may also be downloaded and installed by a user of the portableterminal 330 from a server that provides applications. The server thatprovides applications may include a recording medium in which thecorresponding program is stored.

Referring to FIG. 2A, a guide rail 30 may be installed on a ceiling ofan examination room in which the X-ray imaging apparatus 100 isdisposed, the X-ray source 110 may be connected to the moving carriage40 moving along the guide rail 30 to move the X-ray source 110 to aposition corresponding to the object 1, and the moving carriage 40 andthe X-ray source 110 may be connected via a post frame 50 to adjust aheight of the X-ray source 110 from ground.

Since the X-ray source 110 may be moved automatically or manually, theX-ray imaging apparatus 100 may further include a driving unit such as amotor that provides power to allow the X-ray source 110 to move when theX-ray source 110 automatically moves.

The work station 180 may be provided in a space separated, by ashielding curtain B, from a space in which the X-ray source 110 isdisposed. The work station 180 may include an input unit 181 thatreceives a command from the user and a display 182 that displaysinformation.

The input unit 181 may receive a command for controlling an imagingprotocol, an X-ray irradiation condition, a time point at which X-raysare radiated, a position of the X-ray source 110, and the like. Theinput unit 181 may include a keyboard, a mouse, a touch screen, a voicerecognizer, and the like.

The display 182 may display a screen for guiding an input by the user,an X-ray image, a screen showing a state of the X-ray imaging apparatus100, etc.

Meanwhile, the display 150 and the input unit 160 described withreference to FIG. 1 may be respectively implemented with the input unit181 and the display 182 provided in the work station 180, may also berespectively implemented with a sub-display 81 and a sub-input unit 82provided in the sub-display device 80, and may also be implemented witha display and an input unit provided in a mobile device such as a tabletPC and a smartphone.

The X-ray detector 200 may be implemented with a fixed type X-raydetector fixed to a stand 20 or a table 10, may be detachably mounted onthe mounting units 14 and/or 24, and may also be implemented with aportable X-ray detector which is usable at any position. The portableX-ray detector may be implemented as a wired type or a wireless typeaccording to a way of transmitting data and a way of supplying power.

Since the X-ray detector 200 may also move automatically or manually,the X-ray imaging apparatus 100 may further include a driving unit suchas a motor that provides power to allow the mounting units 14 and 24 tomove when the X-ray detector 200 moves automatically.

The X-ray detector 200 may either be included or not included as anelement of the X-ray imaging apparatus 100. In the latter case, theX-ray detector 200 may be registered in the X-ray imaging apparatus 100by the user. For example, in both cases, the X-ray detector 200 may beconnected to the controller 140 via the communication unit 130 toreceive a control signal or transmit image data.

The sub-display device 80 that provides the user with information andreceives a command from the user may be provided at one side of theX-ray source 110, and some or all of the functions performed by theinput unit 181 and the display 182 of the work station 180 may beperformed by the sub-display device 80.

When all or some of the elements of the controller 140 and thecommunication unit 130 are separately provided from the work station180, the elements may be included in the sub-display device 80 providedat the X-ray source 110.

The user may input various types of information or commands related toX-ray imaging by manipulating the sub-input unit 82 illustrated in FIG.2B or touching the sub-display 81 illustrated in FIG. 2B.

For example, the user may input a position to which the X-ray source 110will be moved through the sub-input unit 82 or the sub-display 81.

Although FIG. 2A illustrates a fixed type X-ray imaging apparatusconnected to a ceiling of an examination room, the X-ray imagingapparatus 100 may include X-ray imaging apparatuses with variousstructures such as a C-arm type X-ray imaging apparatus or a mobileX-ray imaging apparatus within the scope that is self-evident to thoseof ordinary skill in the art.

Meanwhile, the X-ray source 110 may include an X-ray tube that generatesX-rays, a collimator that performs collimation of X-rays generated froman X-ray tube to adjust a region to be irradiated with the X-rays, andthe imaging device 120 that captures a camera image. Since the X-raysource 110 includes an X-ray tube 111, the X-ray source 110 is alsoreferred to as a tube head unit (THU). Hereinafter, this will bedescribed in detail with reference to the drawings.

FIG. 3A is a view illustrating a configuration of a collimator, and FIG.3B is a lateral cross-sectional view of a blade taken along line A-A′ inFIG. 3A.

Referring to FIG. 3A, a collimator 113 may include one or more movableblades 113 a, 113 b, 113 c, and 113 d, and the one or more blades mayabsorb X-rays by being formed of a material having a high bandgap. Anirradiation range of X-rays may be adjusted as the one or more bladesmove, and the collimator 113 may further include a motor that providespower to each of the one or more blades.

The controller 140 calculates a movement amount of each of the one ormore blades corresponding to a set X-ray irradiation region andtransmits a control signal for moving the one or more blades by thecalculated movement amount to the collimator 113.

For example, the collimator 113 may include four blades 113 a, 113 b,113 c, and 113 d, each having a flat plate shape. The first blade 113 aand the third blade 113 c are movable in two directions along an x-axis,and the second blade 113 b and the fourth blade 113 d are movable in twodirections along a y-axis.

For example, each of the four blades 113 a, 113 b, 113 c, and 113 d maymove separately, or the first blade 113 a and the third blade 113 c maymove together as a set, and the second blade 113 b and the fourth blade113 d may move together as a set.

X-rays may be radiated through a slot R formed by the four blades, andcollimation may be performed by passing X-rays through the slot R.Consequently, in an exemplary embodiment, the slot R is referred to as acollimation region, and an X-ray irradiation region signifies a regionin which X-rays that have passed through the collimation region R areincident on the object 1 or the X-ray detector 200.

Referring to FIG. 3B, the collimator 113 is disposed in front of theX-ray tube 111. Here, a direction toward the front of the X-ray tube 111signifies a direction in which X-rays are radiated. An X-ray irradiationregion E of X-rays radiated from a focal point 2 of the X-ray tube 111is limited by the collimator 113, and scattering of the X-rays isreduced.

Among the X-rays radiated from the X-ray tube 111, X-rays incident onthe blades 113 a, 113 b, 113 c, and 113 d are absorbed into the blades,and X-rays that have passed through the collimation region R areincident on the X-ray detector 200. Here, a description will assume thatan object does not exist.

When X-rays scatter in the form of cone beams, the X-ray irradiationregion E is larger than the collimation region R. A desired range of theX-ray irradiation region E may be irradiated with X-rays by thecontroller 140 by adjusting the collimation region R based on a relationbetween the two regions.

Although the collimator 113 has been described as having four blades ina quadrilateral shape in the example above, this is merely an examplethat is applicable to the X-ray imaging apparatus 100, and the number orshape of blades included in the collimator 113 is not limited thereto.

FIG. 4 shows an X-ray source viewed from the front.

Referring to FIG. 4, the collimator 113 may be disposed in front of theX-ray source 110, and the imaging device 120 may be embedded in a regionadjacent to the collimator 113.

The imaging device 120 may capture a video by being be implemented as acamera such as a charge-coupled device (CCD) camera and a complementarymetal oxide silicon (CMOS) camera. Alternatively, the imaging device 120may also capture still images at short intervals.

While the X-ray source 110 captures an X-ray image, the imaging device120 captures a real image. In an exemplary embodiment to be describedbelow, an image captured by the X-ray source 110 will be referred to asan X-ray image, and an image captured by the imaging device 120 will bereferred to as a camera image. The camera image may either include ornot include an object. That is, the camera image may be captured whilethe object 1 is disposed in front of the X-ray detector 200, and thecamera image may also be captured while the object 1 does not exist.

The imaging device 120 may be disposed at a position at which a portionof an object to be imaged by X-rays may be captured. For example, theimaging device 120 may be mounted on the X-ray source 110 in a directionthat is the same as a direction in which X-rays are radiated from theX-ray source 110. When the imaging device 120 is mounted on the X-raysource 110, the user may more easily set settings related to an X-rayimage while looking at a camera image since an offset between a regionshown in the X-ray image and a region shown in the camera image isreduced. A position on which the imaging device 120 is mounted may besuitably determined within a range that minimizes the offset between theregion shown in the X-ray image and the region shown in the camera imageand that does not affect X-ray imaging.

Since a housing 110 a may be formed in front of the collimator 113, thehousing 110 a may be formed with a material such as a transparent resinor glass to minimize its influence on X-rays radiated from the X-raytube 111.

For example, a guideline GL in a cross shape may be displayed on thehousing 110 a. When the X-ray irradiation region E is irradiated withvisible rays by a collimator lamp embedded in the X-ray source 110, ashadow of the guideline GL may be displayed at the center of the X-rayirradiation region E, and the user may intuitively recognize theposition of the X-ray irradiation region E by looking at the shadow ofthe guideline GL.

The imaging device 120 may be mounted on an inner portion of the housing110 a as illustrated in FIG. 4. Alternatively, the imaging device 120may also be mounted on an outer portion of the housing 110 a. Here, theimaging device 120 may be mounted on a bezel provided at a circumferenceof the housing 110 a. However, since an exemplary embodiment of theX-ray imaging apparatus 100 is not limited thereto, the imaging device120 may be mounted on any position so long as an image of an object canbe captured at the position.

For example, the imaging device 120 may also be implemented with astereo camera. In this case, cameras may be disposed at both left andright sides in front of the X-ray source 110. When the imaging device120 is implemented as a stereo camera, information on a depth of thecamera image may be acquired, and, using the depth information, accuracyin image recognition and reliability of various types of informationcalculated based on the camera image may be improved.

FIGS. 5A and 5B are views each illustrating an example of an automaticexposure control (AEC) sensor that may be used in the X-ray imagingapparatus according to an exemplary embodiment.

To prevent an object from being excessively irradiated with X-rays, theX-ray imaging apparatus 100 may perform AEC. For this, an AEC sensormodule 26 that detects a dose of X-rays may be provided in the mountingunit 24 as illustrated in FIG. 5A. Although the AEC sensor module 26 isdescribed using the mounting unit 24 of the stand 20 in this example,the AEC sensor module 26 may also be provided at the mounting unit 14 ofthe table 10.

FIG. 5A shows the mounting unit 24 viewed from the front. The AEC sensormodule 26 may be provided inside the mounting unit 24 and may include aplurality of AEC sensors 26 a, 26 b, and 26 c that independently detecta dose of X-rays. For example, each of the AEC sensors may beimplemented as an ionization chamber.

The most accurate AEC is possible when an AEC sensor is disposed at thecenter of an X-ray imaging portion. Markers Ma, Mb, and Mc thatrespectively show positions of the plurality of AEC sensors 26 a, 26 b,and 26 c may be provided at a surface of the mounting unit 24 toposition the center of the X-ray imaging portion at a positioncorresponding to the AEC sensor or select an AEC sensor disposed at thecenter of the X-ray imaging portion.

Although a total of three AEC sensors, two at an upper side and one at alower side, are illustrated as being provided in FIG. 5A, this is merelyan example. Less than or more than three AEC sensors may also beprovided, and the AEC sensors may also be arranged in a different way.

Referring to FIG. 5B, the AEC sensor module 26 may also be disposed infront of the X-ray detector 200. A direction toward the front of theX-ray detector 200 signifies a direction in which X-rays are incident.FIG. 5B shows the AEC sensor module 26 disposed in front of the X-raydetector 200 viewed from the side.

A current may be generated when X-rays are incident on an AEC sensor,and the AEC sensor may transmit a signal corresponding to the generatedcurrent to the controller 140. The signal transmitted to the controller140 may be an amplified and digitized signal.

Based on the transmitted signal, the controller 140 determines whether adose of X-rays currently incident exceeds a critical dose. When the doseof the X-rays exceeds the critical dose, a cut-off signal may betransmitted to a high-voltage generator 101 that supplies a high voltageto the X-ray tube 111 to stop generation of the X-rays.

Meanwhile, a grid that prevents X-rays from scattering may also bedisposed in front of the AEC sensor module 26. Some of the X-raysradiated from the X-ray source 110 may deviate from their original pathand scatter by colliding against dust particles in the air or substancesforming an object before reaching the X-ray detector 200. When thescattered X-rays are incident on the X-ray detector 200, the scatteredX-rays have a negative influence on the quality of an X-ray image suchas degrading the contrast of an X-ray image.

The grid has a structure in which shielding substances such as lead (Pb)that absorb X-rays are arranged. Among radiated X-rays, X-rays advancingin their original direction, i.e., X-rays moving forward, pass throughportions between the shielding substances and are incident on the X-raydetector 200, and scattered X-rays collide with the shielding substancesand are absorbed into the shielding substances.

The shielding substances may be arranged in a linear structure and alsoin a cross-like structure. For example, the shielding substances may betilted in a direction similar to that in which the X-rays are radiatedand may be densely arranged or arranged in parallel.

Although not illustrated in the drawings, a driving unit that includes amotor which may mechanically move the grid may be disposed inside themounting unit 24. Consequently, an angle or a central position of thegrid may be adjusted by transmitting a control signal to the drivingunit from the outside.

Meanwhile, although the AEC sensor module 26 has been described in theexample as being provided at the mounting unit 24, the AEC sensor module26 may also be integrally provided with the X-ray detector 200.

FIGS. 6 to 10 are views each illustrating an example of a screendisplayed on a display.

Referring to FIG. 6, a settings window 151 for setting an X-rayirradiation condition and a work list 155 may be displayed on a screen150 a of the display 150.

The work list 155 may include a study list 155 a from which a study maybe selected and a protocol list 155 b from which an imaging protocol maybe selected. A study may refer to a set of X-ray images related to eachother. When any one study is selected from the study list 155 a, theprotocol list 155 b from which an imaging protocol to be applied to theselected study may be selected is displayed.

An X-ray imaging region may change for each imaging protocol, and asuitable X-ray irradiation condition may change for each X-ray imagingregion. An imaging protocol may be determined according to a portion tobe imaged by X-rays, a posture of an object, and the like. For example,imaging protocols may include whole body anterior-posterior (AP), wholebody PA, and whole body lateral (LAT), may also include chest AP, chestPA, and chest LAT, and may also include long bone AP, long bone PA andlong bone LAT for long bones such as a leg. For example, imagingprotocols may also include abdomen erect imaging.

A graphical user interface (GUI) may be displayed so that the user canintuitively control the X-ray imaging apparatus 100. The GUI may includea plurality of graphical objects which may be used to set various X-rayirradiation conditions. In an exemplary embodiment, objects such asbuttons and icons displayed on the display 150 to provide information orbe used in receiving a control command from a user may all be referredto as graphical objects.

Since the graphical objects are used in receiving a command for settingan X-ray irradiation condition from the user, the graphical objects maybe implemented with buttons respectively corresponding to the variousX-ray irradiation conditions.

For example, the buttons may include a tube voltage setting button 151 afor receiving a tube voltage setting, a tube current setting button 151b for receiving a tube current setting, and an exposure time settingbutton 151 c for receiving an X-ray exposure time setting, and acurrently set tube voltage, tube current, and exposure time may berespectively displayed at side surfaces of the buttons. The user mayselect each of the buttons to set an X-ray irradiation condition to havea desired value. The buttons may be selected by clicking or touchingdepending on a type of the input unit 160.

According to an exemplary embodiment, the tube voltage setting button151 a may separately include a button for increasing a tube voltage anda button for decreasing the tube voltage, the tube current settingbutton 151 b may separately include a button for increasing a tubecurrent and a button for decreasing the tube current, and the exposuretime setting button 151 c may separately include a button for increasingan exposure time and a button for decreasing the exposure time.

For example, a capture position setting button 151 d for receiving asetting related to whether X-ray imaging will be performed at the stand20 or at the table 10 or whether the portable X-ray detector will beused, an object size selection button 151 e for receiving a selectionrelated to a size of a patient, and a collimator setting button 151 ffor receiving a setting related to a size of the collimator may befurther displayed on the settings window 151.

For example, an AEC selection button 151 g for receiving a selectionrelated to an AEC sensor, a sensitivity setting button 151 h forreceiving a setting related to sensitivity, a density setting button 151i for receiving a setting related to density, a grid selection button151 j for receiving a selection related to the grid, a filter selectionbutton 151 k for receiving a selection related to a filter, a focalpoint selection button 151 r for receiving a selection related to a sizeof a focal point, etc. may be further displayed in the settings window151.

The buttons may be implemented as shapes formed of pictures, letters,symbols, etc. The user may select any one shape by moving a cursor andclicking the corresponding shape or touching and manipulating the shape.Accordingly, a setting corresponding to the selected shape may bechanged.

Meanwhile, when a selection related to a size of a patient is input, anX-ray irradiation condition mapped as a default for the correspondingsize may be set. For this, the storage unit 170 may store a database inwhich an X-ray irradiation condition for each of a plurality of sizes ofa patient is mapped.

When the user selects a size of a patient, X-ray irradiation conditionssuch as a tube voltage, a tube current, and an exposure time mapped as adefault for the corresponding size are displayed in the settings window151. The mapped X-ray irradiation conditions may be applied withoutchange, or the user may select a button corresponding to each of theX-ray irradiation conditions and set each of the X-ray irradiationconditions again according to the method described above. Here, the usermay set each of the X-ray irradiation conditions again with reference todefault X-ray irradiation conditions displayed in the settings window151.

For example, an X-ray imaging region may change for each imagingprotocol, and a suitable X-ray irradiation condition may change for eachX-ray imaging region. Consequently, an X-ray irradiation condition maybe differently set according to an imaging protocol selected from thework list 155 and a size of an object selected from the settings window151.

The types and arrangements of the graphical objects displayed in thesettings window 151 described above are all illustrative. Some of theabove may be omitted according to a designer's choice, a graphicalobject other than the above for changing a setting may be furtherprovided, and the above may be provided in arrangements different fromthose in the example described above.

An “exposure” button 151 l that receives a command related to startingX-ray imaging and a reset button 151 n for initializing with preselectedsettings may be displayed at a lower end of the settings window 151. Theuser may select the “exposure” button 151 l to perform X-ray imaging andmay select the reset button 151 n when attempting to initializesettings.

Meanwhile, to obtain information required for performing X-ray imaging,the imaging device 120 may capture a camera image while the X-ray source110 is facing the X-ray detector 200. In this case, the X-ray detector200 or the mounting units 14 and 24 on which the X-ray detector 200 ismounted may be covered by the object 1 and not be shown in the cameraimage. Conversely, when a camera image is captured while the object 1 isnot disposed in front of the X-ray detector 200, the X-ray detector 200or the mounting units 14 and 24 on which the X-ray detector 200 ismounted may be shown in the camera image. A captured camera image 152may be displayed at one side of the settings window 151 as illustratedin FIG. 7.

The work list 155 illustrated in FIG. 6 and the camera image 152illustrated in FIG. 7 may be switched with each other. The work list 155may be switched to the camera image 152 when a camera image button I isselected while the work list 155 is displayed, and the camera image 152may be switched to the work list 155 when a close button 152 b isselected while the camera image 152 is displayed. Alternatively, whenthe selected imaging protocol needs stitching imaging, the work list 155may be switched to the camera image 152 automatically and then screensregarding stitching imaging described below may be displayed.

Referring to FIGS. 7 to 9, graphical objects showing various types ofinformation may be displayed by being overlaid on the camera image 152.The graphical objects showing various types of information may include,for example, size displaying graphical objects 152 e and 152 f showing asize of the collimation region R, a length displaying graphical object152 g showing the length of the object 1, and a distance displayinggraphical object 152 h showing a distance between the X-ray source 110and the X-ray detector 200 or a distance between the X-ray source 110and the object 1.

The user may control various types of settings related to an operationof the X-ray imaging apparatus 100 with reference to the graphicalobjects displayed by on the camera image 152.

For example, as illustrated in FIG. 7, an irradiation window W showing aregion on which X-rays that have passed through the collimation regionwill be incident, i.e., an X-ray irradiation region, may be displayed bybeing overlaid on the camera image 152, and the user may adjust the sizeof the irradiation window W by dragging at least one of a plurality of aboundary lines that form the irradiation window W or dragging at leastone of a plurality of vertices forming the irradiation window W.

Here, the size of the irradiation window W corresponds to the size ofthe collimation region. However, since a size of an image shown on thedisplay 150 is different from an actual size, it is difficult toaccurately adjust the size of the irradiation window W to fit a captureregion.

Consequently, the display 150 may display the size displaying graphicalobjects 152 e and 152 f illustrating information related to the size ofthe collimation region at a region adjacent to the irradiation window W.

For example, the size displaying graphical object 152 e displayed at anupper portion of the irradiation window W may show the width of thecollimation region with a numerical value 152 e-1, and the sizedisplaying graphical object 152 f displayed at a side portion of theirradiation window W may show the height of the collimation region witha numerical value 152 f-1.

Alternatively, the size of the X-ray irradiation region E may also bedirectly shown. In this case, the controller 140 may calculate the sizeof the X-ray irradiation region E based on information such as thedistance between the X-ray source 110 and the X-ray detector 200, thesize of the collimation region, and the distance between the X-ray tube111 and the slot R of the collimator 113.

The user may refer to size information shown by the size displayinggraphical object 152 f for changing the size of the collimation region.To change the size of the collimation region, the boundary lines orvertices of the irradiation window W may be dragged as described aboveor a section in which the camera image 152 is displayed or a surroundingportion thereof may be touched or clicked to allow an input window (notshown) for changing the height or width of the collimation region to bedisplayed. When the input window is displayed, a numerical value of adesired height or width may be input to adjust the size of thecollimation region.

For example, when a captured X-ray image does not include the wholeportion desired to be imaged and thus imaging is performed again, theuser may refer to the size information provided by the size displayinggraphical object 152 e to determine how much larger the imaging regionhas to be compared to the previous imaging.

For example, to guide the re-imaging, a previous irradiation window Wpcorresponding to the size of the collimation region that has beenapplied to the previous imaging and a current irradiation window Wc tobe applied to the re-imaging may be displayed together on the cameraimage 152 as illustrated in FIG. 8. The previous irradiation window Wpmay remain displayed even when the user changes the size of the currentirradiation window Wc for the re-imaging, and the user may refer to thedisplayed previous irradiation window Wp to determine an amount by whichthe size of the collimation region will be increased. Here, the previousirradiation window Wp and the current irradiation window Wc may bedistinguished from each other by displaying the previous irradiationwindow Wp with a dotted line or displaying the previous irradiationwindow Wp to be blurrier than the current irradiation window Wc.

An “apply” button 152 a for applying the adjusted size of thecollimation region to X-ray imaging and a “close” button 152 b to stopdisplaying the camera image 152 may be provided at the lower end of thecamera image 152. For example, a cancel button (not illustrated) forcancelling various types of applied settings may also be provided at thelower end of the camera image 152. The user may select at least one ofthe “apply” button 152 a, the “close” button 152 b, and the cancelbutton, and a command corresponding to the user's selection may be inputand transmitted to the controller 140.

When the “apply” button 152 a is selected, a control commandcorresponding to the adjusted size of the collimation region istransmitted to the collimator 113, and the collimator 113 moves theblades 113 a, 113 b, 113 c, and 113 d according to the transmittedcontrol command to adjust the size of the collimation region.

Meanwhile, when stitching imaging is performed, a top line L_(T) and abottom line L_(B) may be displayed by being overlaid on the camera image152, as illustrated in FIG. 9. The top line L_(T) may show the top ofthe stitching region, and the bottom line L_(B) may show the bottom ofthe stitching region. The stitching imaging may be performed in a regionbetween the top line L_(T) and the bottom line L_(B).

The top line L_(T) and the bottom line L_(B) may be initially displayedat any position on the camera image 152 or, when an imaging protocol isselected, may be displayed at positions corresponding to the selectedimaging protocol.

When the top line L_(T) and the bottom line L_(B) are displayed at anyposition on the camera image 152, the bottom line L_(B) may be disposedat a lower end portion of the camera image 152. Since an object's toe isdisposed at the lower end portion of the camera image 152 regardless ofthe size of the object, a work load of the user may be reduced when thebottom line L_(B) is disposed at the lower end portion of the cameraimage 152 since the user does not have to manipulate the input unit tomove the bottom line L_(B).

When the top line L_(T) and the bottom line L_(B) are displayed atpositions corresponding to an imaging protocol, the controller 140 mayperform image processing such as applying an object recognitionalgorithm to the camera image 152 to recognize a portion correspondingto the imaging protocol.

The user may drag at least one of the top line L_(T) and the bottom lineL_(B) to change a position thereof. For example, the user may drag andmove at least one of the top line L_(T) and the bottom line L_(B) upwardor downward.

For example, a length displaying graphical object 152 g showing anabsolute length of an object shown in the camera image may be displayedby being overlaid on the camera image 152.

Specifically, the length displaying graphical object 152 g is providedto allow the user to easily recognize the length of the object 1displayed on the camera image 152 or a length of each of the dividedregions S₁, S₂, and S₃ within the camera image 152. Here, the dividedregions S₁, S₂, and S₃ are regions divided from the entire or partialregion S of the camera image 152, and the partial region of the cameraimage 152 may include the region between the top line L_(T) and thebottom line L_(B).

The length displaying graphical object 152 g may be displayed in theform of a tool that measures a length using a plurality of scales, e.g.,a ruler. The scales are indices for discretely showing a length and mayinclude first scales 152 g-1 which are relatively long and second scales152 g-2 which are relatively short.

The first scales 152 g-1 are disposed in equal intervals, and likewise,the second scales 152 g-2 are also disposed in equal intervals. Aplurality of second scales 152 g-2, e.g., four or nine second scales 152g-2, are disposed between each of the first scales 152 g-1.

For example, at a region adjacent to a scale, a length shown by thecorresponding scale may be displayed as a numerical value. The displayednumerical value may show the actual length, i.e., an absolute length, ofthe object. Here, the reference object is the object 1. A scale betweena size in real space and a size in the camera image 152 may be reflectedin the intervals between the scales.

The controller 150 may calculate the intervals between the scalesincluded in the length displaying graphical object 152 g and numericalvalues respectively shown by the scales based on a source-to-objectdistance (SOD) between the object 1 and the X-ray source 110 or asource-to-image distance (SID) between the X-ray detector 200 and theX-ray source 110. For example, when the SOD or SID changes due to amovement of the X-ray source 110, the controller 140 may calculate thechange in real time and update the intervals between the scales and thenumerical values respectively shown by the scales based on the change.The updated intervals between the scales and the numerical valuesrespectively shown by the scales may be reflected in the lengthdisplaying graphical object 152 g displayed by being overlaid on thecamera image 152.

The user may easily estimate the length of the object 1 displayed on thecamera image 152 with reference to the length displaying graphicalobject 152 g. For example, the user may easily recognize an absoluteheight or relative height of the whole stitching region S or each of thedivided regions S₁, S₂, and S₃ within the whole stitching region S withreference to the length displaying graphical object 152 g.

For example, as in the example described above, when a captured X-rayimage does not include the whole portion desired to be imaged and thusimaging is performed again, the user may refer to length informationprovided by the length displaying graphical object 152 g to determinehow much larger the imaging region has to be compared to the previousimaging

For example, to guide the re-imaging, a previous top line L_(T) and aprevious bottom line L_(B) that has been applied to the previous imagingand a current top line L_(T) and a current bottom line L_(B) to beapplied to the re-imaging may be displayed by being overlaid on thecamera image 152 together. The previous top line L_(T) and the previousbottom line L_(B) may remain to be displayed even when the user changespositions of the current top line L_(T) and the current bottom lineL_(B) for the re-imaging, and the user may determine positions of thecurrent top line L_(T) and the current bottom line L_(B) with referenceto the displayed previous top line L_(T) and previous bottom line L_(B)and the length displaying graphical object 152 g. Here, the previous topline L_(T) and the previous bottom line L_(B) may be distinguished fromthe current top line L_(T) and the current bottom line L_(B) bydisplaying the previous top line L_(T) and the previous bottom lineL_(B) with dotted lines or displaying the previous top line L_(T) andthe previous bottom line L_(B) to be blurrier than the current top lineL_(T) and the current bottom line L_(B).

For example, a distance displaying graphical object 152 h may bedisplayed by being overlaid on the camera image 152 as illustrated inFIG. 10.

The distance displaying graphical object 152 h shows the SID or SOD.

The distance displaying graphical object 152 h may be overlaid anddisplayed at one point of the camera image 152, e.g., at a lower leftend of the camera image 152. The distance displaying graphical object152 h may show the SID or SOD using letters, symbols, or numbers.

When the user touches or clicks a region in which the distancedisplaying graphical object 152 h is displayed or a surrounding portionthereof, an input window (not illustrated) for adjusting the SID or SODmay be displayed. The user may directly input values in the input windowor input a value of a desired distance by clicking or touching. When theuser inputs a predetermined value, the controller 140 may move at leastone of the X-ray source 110 and the X-ray detector 200 according to theinput value.

Hereinafter, several examples of a method for measuring a distancebetween the X-ray source 110 and the X-ray detector 200 will bedescribed. Although only the method for measuring a distance between theX-ray source 110 and the X-ray detector 200 will be described below, adistance between the object 1 and the X-ray source 110 may also bemeasured using the same or a similar method.

FIGS. 11A to 11C are views for describing an example of a method formeasuring a distance between an X-ray detector and an X-ray source.

Referring to FIG. 11A, when moving the X-ray source 110 and the X-raydetector 200 is completed, the controller 140 may determine a position Pof the X-ray source 110 and a position Q of the X-ray detector 200. Inthis case, the controller 140 may determine the position P of the X-raysource 110 or the position Q of the X-ray detector 200 using an encoderthat measures a number of rotations of a motor used in a movement of theX-ray source 110 and a movement of the X-ray detector 200 or using aseparate position detector, e.g., an infrared sensor.

The position P of the X-ray source 110 and the position Q of the X-raydetector 200 may be expressed using predetermined coordinates, and thecontroller 140 may compute a distance between the X-ray source 110 andthe X-ray detector 200 using coordinates P(x,y,z) of the position P ofthe X-ray source 110 and coordinates Q(x,y,z) of the position Q of theX-ray detector 200.

In a detailed example, the controller 140 may compute a differencebetween the coordinates P(x,y,z) of the position P of the X-ray source110 and the coordinates Q(x,y,z) of the position Q of the X-ray detector200 and compute a square root of a sum of squares of the computeddifferences to acquire the distance between the X-ray source 110 and theX-ray detector 200.

In another example, according to FIG. 11B, visible rays reflected from asurface of the mounting unit 24 pass through a lens of the imagingdevice 120 and are incident on an image pickup surface P formed by animage pickup device. The lens may focus the visible rays passingtherethrough to a predetermined focal point o. Light incident on theimage pickup surface P is converted into an electrical signal by theimage pickup device, and converted electrical signals may be combined toacquire an image i corresponding to the image pickup surface P. Themounting unit 24 may be shown in the acquired image i as illustrated inFIG. 11C.

In this case, the distance between the X-ray detector 200 and the X-raysource 100 may be acquired using a numerical value, e.g., a height h1 orwidth, related to the mounting unit 24 shown in the image i.Specifically, since a distance d0 between the image pickup surface P andthe focal point o is a value given according to a hardware feature or asoftware feature of the imaging device 120, e.g., a camera device, andthe height h1 of the mounting unit 24 in the image pickup surface P mayalso be acquired by being directly measured, an angle θ between a lineconnecting an upper end of the mounting unit 24 in the image pickupsurface P to the focal point o and a line connecting the center of themounting unit 24 in the image pickup surface P to the focal point o maybe computed.

Meanwhile, since the actual height h0 of the mounting unit 24 is also agiven value, a distance d0+d1 between the focal point o and the mountingunit 24 may be computed using a half h0/2 of the actual height h0 of themounting unit 24 and the computed angle θ, and a distance d1 between theimage pickup surface P and the mounting unit 24 may be computed andacquired using the computed distance d0+d1 between the focal point o andthe mounting unit 24. The distance between the X-ray detector 200 andthe X-ray source 110 is acquired since the distance d1 between the imagepickup surface P and the mounting unit 24 is substantially or almost thesame as the distance between the X-ray detector 200 and the X-ray source110.

The above-described methods of acquiring the distance between the X-raydetector 200 and the X-ray source 110 are non-limiting examples only,and the distance between the X-ray detector 200 and the X-ray source 110may be acquired using other appropriate methods.

Information on the distance between the X-ray detector 200 and the X-raysource 110 acquired as above may be provided to the user as describedabove.

Any one of the graphical objects 152 e, 152 f, 152 g, and 152 hdescribed above may be exclusively displayed or all or several graphicalobjects 152 e, 152 f, 152 g, and 152 h may be displayed together on thescreen 150 a of the display 150. Types of the graphical objects beingdisplayed, positions at which the graphical objects are displayed, andwhether a graphical object is solely displayed, etc. may be determinedin various ways according to predefined settings or manipulation by theuser.

Meanwhile, when X-ray imaging portion of the object is larger than theX-ray irradiation region E or a detection region in which the X-raydetector 200 may detect X-rays, the X-ray imaging portion may be dividedinto a plurality of regions, X-ray imaging may be separately performedfor each of the plurality of divided regions. Obtaining a single entireX-ray image by dividing the X-ray imaging portion into a plurality ofregions, imaging each of the plurality of divided regions and stitchingthe X-ray images for each of the plurality of divided regions may bereferred to by various terms such as panoramic imaging, stitchingimaging, segmentation imaging, etc. For convenience of description, suchimaging (panoramic imaging, stitching imaging, segmentation imaging,etc.) will be referred to as stitching imaging, in the exemplaryembodiments. Also, each of the X-ray images for each of the dividedregions will be referred to as divided X-ray image and each of the X-rayimaging for each of the divided regions will be referred to as dividedimaging. Furthermore, one image generated by stitching together aplurality of divided X-ray images will be referred to as a stitchedimage.

FIG. 12A is a view illustrating an example of a stitched-together image,FIG. 12B is a view illustrating an example in which an imaging region isdivided to perform stitching imaging, and FIG. 12C is a viewillustrating overlapping regions between each of a plurality of dividedregions. FIGS. 12D and 12E are views illustrating an operation in whichoverlapping regions are automatically adjusted.

As illustrated in FIG. 12A, the X-ray imaging apparatus 100 may dividean X-ray imaging portion into a plurality of regions and may separatelyperform X-ray imaging for each of the plurality of divided regions.

The controller 140 may stitch X-ray images of divided regions, i.e.,divided X-ray images X₁, X₂, and X₃, together to generate onestitched-together image X₁₂₃ showing a whole X-ray imaging portion. Inan exemplary embodiment, an entire region in which stitching imaging isto be performed will be referred to as a stitching region.

As described above, when the selected imaging protocol corresponds tothe stitching imaging, the work list 155 may be switched to the cameraimage 152 illustrated in FIG. 12B. Also, an imaging region correspondingto the selected imaging protocol may be automatically designated as thestitching region. The controller 140 may automatically divide thestitching region. For example, the controller 140 may divide thestitching region into uniform sizes, i.e., equal sizes, based on thesmaller among height of the detection region and a maximum height of theX-ray irradiation region.

In a detailed example, when a value obtained by dividing a height of astitching region S, i.e., a distance between a top line L_(T) showing apoint where the stitching region begins and a bottom line L_(B) showinga point where the stitching region ends, by a height of the region to bedetected by the X-ray detector 200 is an integer, the solution maybecome the number of divided regions, i.e., the number of divided X-rayimages, used in stitching imaging. On the other hand, when the value isnot an integer, the number of divided regions is larger than thesolution by one, and a height of each of the divided regions is smallerthan the height of the region to be detected by the X-ray detector 200.

For example, as illustrated in FIG. 12B, when the stitching region S isdivided into three divided regions S₁, S₂, and S₃, three divided X-rayimages respectively corresponding to the divided regions may becaptured, and then the three divided X-ray images may be stitchedtogether to generate one stitched-together X-ray image.

Boundary portions between each of the divided X-ray images may bematched to stitch the divided X-ray images together, and X-rays may beradiated so that predetermined regions between the divided X-ray imagesoverlap each other for the matching. When designations of the dividedregions are completed, the controller 140 may control the collimator 113to radiate X-rays to the divided regions such that X-rays is radiated toa range expanded from a divided region toward adjacent divided regionsby a predetermined size.

As an example illustrated in FIG. 12C, X-rays may be radiated so that afirst-to-second overlapping region O₁₂ is disposed between the firstdivided region S₁ and the second divided region S₂, and asecond-to-third overlapping region O₂₃ is disposed between the seconddivided region S₂ and the third divided region S₃.

Since the overlapping regions O₁₂ and O₂₃ are redundantly irradiatedwith X-rays, when a radiosensitive portion such as a genital organ orthe heart is disposed in the overlapping regions, the controller 140 maymove the overlapping regions to other portions to avoid redundantlyirradiating the radiosensitive portion with X-rays or may output awarning to the user.

Whether a radiosensitive portion is disposed in the overlapping regionsmay also be determined by applying image processing such as an objectrecognition algorithm to the camera image 152. For example, a portiondisposed at a central portion of a length from head to toe and fromwhich thighs originate may be determined as a portion at which a genitalorgan is disposed, and a portion spaced apart 20 cm or less downwardfrom armpit portions or shoulders may be determined as a portion atwhich the heart is disposed.

Information related to a radiosensitive portion, e.g., information on aposition or form thereof, may be pre-stored in the storage unit 170 ormay also be added or modified by the user.

When outputting a warning, the warning may be visually output throughthe display 150 or audibly output through a speaker provided in theX-ray imaging apparatus 100. When the warning is visually output, theoverlapping regions may be directly displayed on the display 150 asillustrated in FIG. 12C, or text informing that the overlapping regionsare disposed at a radiosensitive portion may be displayed on the display150. Since the information simply needs to be conveyed, a method ofoutputting a warning is not limited.

The overlapping regions may be distorted in the stitched image and imagequality of the overlapping regions in the stitched image may bedegraded. Thus, the user may determine whether the overlapping portionsare important portions in an X-ray image that need to be protected fromdegradation of image quality based on the provided information relatedto the overlapping regions.

With reference to FIG. 12C described above, a case in which thefirst-to-second overlapping region O₁₂ is disposed at a heart portionand the second-to-third overlapping region O₂₃ is disposed at a genitalregion portion is assumed.

As illustrated in FIG. 12D, the controller 140 may move a lower boundaryof the first divided region S₁ downward so that the first-to-secondoverlapping region O₁₂ is disposed below the heart portion ({circlearound (1)}→{circle around (1)}′) and may move a lower boundary of thesecond divided region S₂ downward so that the second-to-thirdoverlapping region O₂₃ is disposed below the genital organ portion({circle around (2)}→{circle around (2)}′).

Since a start point and an end point of the stitching region S areunchanged, the stitching region S does not change. Consequently, when asize of the first divided region S₁ exceeds a size of the region to bedetected by the X-ray detector 200 or the maximum height of X-rayirradiation region due to the movement of the lower boundary of thefirst divided region S₁, or when a size of the second divided region S₂exceeds the size of the region to be detected by the X-ray detector 200or the maximum X-ray irradiation region due to the movement of the lowerboundary of the second divided region S₂, the first divided region S₁ orthe second divided region S₂ may be further divided or the entirestitching region S may be further divided into smaller regions, and thenoverlapping regions may be re-controlled.

Alternatively, when a fact that overlapping regions are disposed atradiosensitive portions is output visually or audibly as describedabove, the overlapping region may also be adjusted by the user. In thiscase, radiosensitive portions 152 c may be displayed on the camera image152 as illustrated in FIG. 12E to guide the user to reset theoverlapping regions by avoiding the radiosensitive portions. Forexample, the user may move the overlapping regions displayed on thedisplay 150 or move boundary lines of a plurality of divided regions toreset the overlapping regions.

FIGS. 13 and 14 are views illustrating an example of a screen displayedby the display of the X-ray imaging apparatus according to an exemplaryembodiment, for receiving a designation related to a region in whichstitching imaging will be performed, and FIG. 15 is a view illustratingan example of a screen providing information on the length of astitching region.

According to an exemplary embodiment, the X-ray imaging apparatus 100may automatically perform stitching imaging in a designated region whenthe user designates the stitching region through the input unit 160.Hereinafter, this will be described in detail.

To perform X-ray imaging, the imaging device 120 captures a camera imagewhile the object is disposed in front of the X-ray detector. Thecaptured camera image 152 may be displayed on the display 150 asillustrated in FIGS. 13 and 14. For example, the camera image 152 may bedisplayed in real time.

First, a process of designating a stitching region will be described.

The display 150 may display the top line L_(T) designating a point wherethe stitching region begins and the bottom line L_(B) designating apoint where the stitching region ends on the camera image 152. Asdescribed above, the top line L_(T) and the bottom line L_(B) may beinitially displayed at any position on the camera image 152 or may bedisplayed at positions corresponding to a selected imaging protocol.

Alternatively, only one of the top line L_(T) and the bottom line L_(B)may be displayed and the other one may be determined by designation ofthe number of divided imaging.

By viewing the camera image 152, the user may intuitively recognize thenumber of divided imaging operations necessary for acquiring a stitchedimage of the imaging region. In this aspect, the display 150 isconfigured to allow the user to intuitively and conveniently recognizethe optimal number of divided imaging operations, thereby preventingexcessive X-ray irradiation.

The user may manipulate the input unit 160 to adjust positions of thetop line L_(T) and the bottom line L_(B). To guide the manipulation bythe user, the display 150 may display the cursor C, and the cursor C maymove on the screen displayed on the display 150 according to themanipulation of the input unit 160 by the user.

In a case in which the input unit 160 is a mouse, a trackball, or akeyboard, when the user manipulates the mouse, the trackball, or thekeyboard, the cursor C moves according to a direction and a movementamount corresponding to the manipulation. In a case in which the inputunit 160 is a touch pad, the cursor C moves according to a direction inwhich the user's finger moves and a movement amount of the user'sfinger.

For example, the user may drag the top line L_(T) or the bottom lineL_(B) to move the top line L_(T) or the bottom line L_(B) to a desiredposition as illustrated in FIGS. 13 and 14. The top line L_(T) and thebottom line L_(B) may move in the vertical direction or in alongitudinal direction of the object. The stitching region S may bedefined by the top line L_(T) and the bottom line L_(B). That is, aregion between the top line L_(T) and the bottom line L_(B) may be thestitching region S.

When the stitching region S is designated, the controller 140 mayautomatically divide the stitching region S. The controller 140 mayperform uniform division based on a region to be detected by the X-raydetector 200 and the stitching region S defined by the top line L_(T)and the bottom line L_(B).

The controller 140 may perform real-time uniform division every time thetop line L_(T) and the bottom line L_(B) move, and show the result. Forexample, when the stitching region S is divided into four regions S₁,S₂, S₃, and S4 as illustrated in FIG. 13, the regions may be dividedusing guide lines such as a dotted line, and the lines dividing theregions may be numbered from 1 to 4 to provide information on the totalnumber of divided regions and a number assigned to a correspondingdivided region.

As shown in FIG. 12E, the first guideline {circle around (1)} may be abottom limit for a maximum region for which an X-ray image is to beacquired by performing a single X-ray imaging. The second guideline{circle around (2)} may be a bottom limit for a maximum region for whichan X-ray image is to be acquired by performing an X-ray imaging twice.The third guideline {circle around (3)} may be a bottom limit for amaximum region for which an X-ray image is to be acquired by performingan X-ray imaging three times. The fourth guideline {circle around (4)}may be a bottom limit for a maximum region for which an X-ray image isto be acquired by performing an X-ray imaging four times.

For example, when the user has dragged the bottom line L_(B) toward thetop line L_(T) as illustrated in FIG. 14, the controller 140 mayre-execute the real-time uniform division. When the stitching region Sis reduced and divided into three regions S₁, S₂, and S₃, the guidelines dividing the regions may be numbered from 1 to 3 to inform thatthe stitching region is divided into a total of three regions.

Also, to emphasize that the number of divided imaging has changed, thedisplay 150 may display the fourth guideline {circle around (4)}, so asto be distinguished from the remaining first through third guidelines{circle around (1)} through {circle around (3)}. For example, the fourthguideline {circle around (3)} may be displayed as a dotted line, may beblurred or displayed in a different color. However, exemplaryembodiments are not limited thereto, and the fourth guideline 12-4 maybe displayed in different ways to be distinguished from the remainingfirst through third guidelines {circle around (1)} through {circlearound (3)}.

When the designation of the stitching region is completed, the user mayselect apply button 152 a and when the apply button 152 a is selected,the display 150 may display divided window W1, W2, W3 on the cameraimage 152 described below.

For example, when the control command, which indicates the moving thetop line L_(T) or the bottom line L_(B), is input again while thedivided window is displayed, the present screen including the dividedwindow may be switched to the previous screen including guide lines sothat the stitching region or the divided regions are re-designated.

Meanwhile, as mentioned above, the controller 140 may perform uniformdivision based on the height h_(s) of the stitching region S. Here,information related to the height h_(s) of the stitching region S may bedisplayed on the display 150 to be provided to the user. For example, asillustrated in FIG. 15, the height h_(s) of the stitching region S maybe displayed as a number on the camera image 152. Here, a height h_(T)of the top line L_(T) from ground and a height h_(B) of the bottom lineL_(B) from ground may also be displayed together with the height of thestitching region.

The controller 140 may calculate the heights h_(s), h_(T), and h_(B)based on a distance between the imaging device 120 and the X-raydetector 200 or a distance between the imaging device 120 and the object1.

For example, the controller 140 may pre-store relations between animaging device coordinate system based on the imaging device 120, aglobal coordinate system of a space in which the X-ray imaging apparatus100 is disposed, and a two-dimensional coordinate system of the cameraimage, and use conversions between the coordinate systems to calculatean actual height of the stitching region displayed on the camera image.

For example, the controller 140 may calculate the heights h_(s), h_(T),and h_(B) changing according to a movement of the top line L_(T) or thebottom line L_(B) in real time and provide the calculated heights h_(s),h_(T), and h_(B) to the user.

As described above, when information related to the size of thestitching region S is provided through the display 150, the user mayintuitively recognize the size of the stitching region S and set thestitching region S or use the information as reference in setting anX-ray irradiation condition.

Although the controller 140 has been described in the exemplaryembodiment above as dividing the stitching region S into equal sizes, anexemplary embodiment of the X-ray imaging apparatus 100 is not limitedthereto. The sizes of the divided regions may also be adjusted to bedifferent from each other, and the user may directly designate each ofthe divided regions. The user may designate the start point and endpoint of each divided region. If it is desired to split the wholestitching region S into three divided regions, a start point and an endpoint of a first divided region S₁, a start point and an end point of asecond divided region S₂, and a start point and an end point of a thirddivided region S₃ may be designated.

If a designation of stitching imaging regions is performed by directlymoving a large X-ray source, which may make it difficult for a user toprecisely designate the stitching regions and may cause severe fatigueto the user.

According to the above embodiments, the X-ray imaging apparatus mayprecisely designate stitching regions and may reduce user fatigue.

For example, repetitive irradiation of an important body part withX-rays may be prevented by adjusting overlapping regions automaticallyor manually.

When setting the stitching region is completed, the user may select the“apply” button 152 a to finish setting the stitching region and may setan X-ray irradiation condition for each of the divided regions.

For example, when the “apply” button 152 a is selected, a plurality ofdivided windows W1, W2, and W3, e.g., GUIs, may be displayed, and eachof the divided windows may be displayed by interoperating with thesettings window 151 as will be described below.

In another example, each of the divided windows may interoperate withthe settings window 151 and receive a setting of an X-ray irradiationcondition before the “apply” button 152 a is selected and even when thedivided windows W1, W2, and W3 are not displayed.

FIGS. 16A to 19 are views illustrating a screen that allows a user toset an X-ray irradiation condition for each of a plurality of dividedregions.

Although the same X-ray irradiation condition may be set for each of theplurality of divided regions, there are cases, including when featuresof an object shown in the divided regions are different from each other,when X-ray irradiation conditions need to be set differently.

When designating the stitching region S is completed, the dividedwindows W1, W2, and W3 respectively corresponding to the divided regionsmay be displayed by being overlaid on the camera image 152 asillustrated in FIG. 16A. Each of the divided windows may include aplurality of boundary lines, and the plurality of boundary lines mayhave shapes corresponding to boundaries of the blades 113 a, 113 b, 113c, and 113 d of the collimator 113. Consequently, the divided windowsW1, W2, and W3 may have, for example, a square shape or a rectangularshape.

The first divided window W1 corresponds to the first divided region, thesecond divided window W2 corresponds to the second divided region, andthe third divided window W3 corresponds to the third divided region

Alternatively, as illustrated in FIG. 16B, the display 150 may displaythe divided windows W1, W2 and W3, adjacent ones of which partiallyoverlap each other, over the camera image 152. The first and seconddivided windows W1 and W2 may overlap each other to representoverlapping region O₁₂ between the first divided region S₁ and thesecond divided region S₂, and the second and third divided windows W2and W3 may overlap each other to represent overlapping region O₂₃between the second divided region S₂ and the third divided region S₃.

The size of each of the divided windows corresponds to the size of eachof the divided regions, and the width of each of the divided regionscorresponds to width of the collimation region R or the X-rayirradiation region E. In this example, a case in which X-ray irradiationregions of the same width are applied to all of the divided regions willbe described.

The height of each of the divided regions may be determined according todivision of the region S by the controller 140 or the user, and the sizeof the collimation region may be automatically adjusted according to theheight of each of the divided regions. Alternatively, as described abovewith reference to changing the irradiation window W, by clicking,touching, or clicking or touching then dragging at least one of upperboundary lines and lower boundary lines of the divided windows W1, W2,and W3, the user may change a position of a corresponding boundary line,and a divided region changes according to the changed position of thecorresponding boundary line. The blades of the collimator 113 may movecorresponding to the changed divided windows W1, W2, and W3.

Meanwhile, by changing a length of just one of the divided regions,heights of other divided regions which are not changed may increase ordecrease when lengths of all of the divided regions are the same. Whenchanges are made to only some of the plurality of divided regions by theuser, the controller 140 may automatically change lengths of theremaining divided regions and control the collimator 113 according tothe changed lengths.

As illustrated in FIG. 16A, information on the size of each of thedivided windows W1, W2, and W3 may be displayed by being overlaid on thecamera image 152. For this, the size displaying graphical objects 152 eand 152 f described above may be used, and the description of theirradiation window W may be identically applied to that of each of thedivided windows W1, W2, and W3. However, a size of only the selecteddivided window W2 may be displayed as illustrated in FIG. 16, or sizesof all of the divided windows W1, W2, and W3 may also be displayedregardless of the selection.

Meanwhile, a GUI, through which an X-ray irradiation condition for eachof the divided regions may be set, may be displayed on the settingswindow 151. For this, an identification tab 151 p used in selecting thedivided regions may be displayed at an upper end of the settings window151, and the identification tab 151 p may be provided for each of thedivided regions. Identification tags #1, #2, and #3 respectivelycorresponding to the divided windows W1, W2, and W3 may be displayed onidentification tabs 151 p-1, 151 p-2, and 151 p-3, respectively.

When the user manipulates the input unit 160 and selects one of theidentification tabs 151 p-1, 151 p-2, and 151 p-3, a GUI through whichan X-ray irradiation condition for a divided region corresponding to theselected identification tab may be set may be activated.

As in the example illustrated in FIG. 17, when the user moves the cursorC and selects the identification tab 151 p-1 corresponding to the firstdivided region S₁, the camera image 152 may interoperate therewith, andthe first divided window W1 displayed on the camera image 152 may behighlighted. That is, a selection of the divided region performed in thesettings window 151 may also be reflected in the camera image 152. Thepurpose of the highlighting is to intuitively show the divided regioncurrently selected by the user. For example, an edge of the firstdivided window W1 may be displayed in dark color. Alternatively, an edgeof a selected divided window may also be highlighted by being displayedin different color or flickered, and a way of displaying a selecteddivided window is not limited.

Alternatively, the user may directly select a divided region whose X-rayirradiation condition will be set on the camera image 152. As in theexample illustrated in FIG. 18, the user may move the cursor C andselect the second divided window W2 displayed on the camera image 152.The settings window 151 may interoperate therewith, the identificationtab 151 p-2 corresponding to the second divided region S2 in thesettings window 151 may be automatically selected, and a GUI throughwhich an X-ray irradiation condition for the second divided region S2may be set may be activated.

Meanwhile, as illustrated in FIG. 19, identification tags 152 c-1, 152c-2, and 152 c-3 respectively matching the identification tags #1, #2,and #3 displayed on the settings window 151 may be displayed also on thedivided windows W1, W2, and W3 displayed on the camera image 152.

The user may look at the identification tags 152 c-1, 152 c-2, and 152c-3 respectively displayed on the divided windows W1, W2, and W3 andintuitively recognize a divided region whose X-ray irradiation conditionmay be set by the GUI activated in the settings window 151.Particularly, since upper and lower sides are not distinguished whenX-ray imaging is performed on the table 10, it may be difficult torecognize matching relations between the divided windows W1, W2, and W3displayed on the camera image 152 and the identification tags #1, #2,and #3 displayed on the settings window 151 in some cases. When theidentification tags 152 c-1, 152 c-2, and 152 c-3 respectively matchingthe identification tags #1, #2, and #3 displayed on the settings window151 are displayed as in this example, the user may accurately set anX-ray irradiation condition without getting confused.

For example, when the first identification tag #1 is selected from thesettings window 151 or the first divided window W1 is selected from thecamera image 152 to set an X-ray irradiation condition for the firstdivided region S₁, the user may look at the first identification tag #1displayed on the settings window 151 and the first identification tag152 c-1 displayed on the camera image 152 and easily check that thefirst divided region is a divided region currently targeted for settingan X-ray irradiation condition.

Although the case in which the identification tag displayed on thesettings window 151 and the identification tag displayed on the cameraimage 152 are the same has been described in this example, an exemplaryembodiment is not limited thereto. The identification tags differentfrom each other may also be used so long as the user can recognize thatthe two identification tags match.

FIGS. 20 to 23 are views illustrating an example of a graphical userinterface that allows making a selection of an X-ray irradiationcondition to be directly performed on a camera image.

In the example described above, a case has been described as an example,in which inputs related to settings of tube voltage, tube current, X-rayexposure time, etc. are received by buttons displayed on the settingswindow 151.

According to another example illustrated in FIG. 20, the display 150 maydisplay a graphical object capable of receiving settings related to atube voltage, a tube current, and an X-ray exposure time at a regionadjacent to the divided window W1 on the camera image 152. In thisexample, a description will be given by assuming that the graphicalobject is a setting button.

One of the tube voltage, the tube current, and the X-ray exposure timemay be selected as default, and an X-ray irradiation condition to be setmay also be determined by the user selecting one of a region in whichthe tube voltage is displayed, a region in which the tube current isdisplayed, and a region in which the X-ray exposure time is displayedfrom the settings window 151. In the example shown in FIGS. 20 to 23, acase in which a tube voltage setting is received will be described.

Specifically, when a divided region targeted for setting a tube voltageis determined by selecting one of the plurality of tabs displayed on thesettings window 151 or selecting one of a plurality of divided windowsdisplayed on the camera image 152, the setting button 152 d forreceiving a setting related to the tube voltage of the correspondingdivided region may be displayed at a region adjacent to the selecteddivided window W1. The setting button 152 d may also be displayed withinor outside the divided window W1.

When the user manipulates the setting button 152 d and inputs a commandfor increasing the tube voltage as illustrated in FIG. 21, the tubevoltage may be set according to the input command, and a numerical valueof the tube voltage displayed on the settings window 151 also increasescorresponding to the input command.

For example, as illustrated in FIG. 22, when the user manipulates thesetting button 152 d and inputs a command for decreasing the tubevoltage as illustrated in FIG. 22, the tube voltage may be set accordingto the input command, and a numerical value of the tube voltagedisplayed on the settings window 151 also decreases corresponding to theinput command. That is, manipulation of the setting button 152 d and thescreen displayed on the settings window 151 are synchronized with eachother.

Meanwhile, as illustrated in FIG. 23, a tube voltage setting button 152d-1 for receiving a setting command related to a tube voltage, a tubecurrent setting button 152 d-2 for receiving a setting command relatedto a tube current, and an exposure time setting button 152 d-3 forreceiving a setting command related to an X-ray exposure time may alsobe separately displayed.

The user may manipulate each of the setting buttons 152 d-1, 152 d-2,and 152 d-3 to input a setting command related to an X-ray irradiationcondition that is desired to be set, and a numerical value displayed onthe settings window 151 also changes according to the input command.

For example, when the user manipulates the tube voltage setting button152 d-1 and inputs a setting command related to a tube voltage, anumerical value of a tube voltage displayed on the settings window 151is synchronized with the input command. When the user manipulates thetube current setting button 152 d-2 and inputs a setting command relatedto a tube current, a numerical value of a tube current displayed on thesettings window 151 is synchronized with the input command. When theuser manipulates the exposure time setting button 152 d-3 and inputs asetting command related to an X-ray exposure time, a numerical value ofan X-ray exposure time displayed on the settings window 151 issynchronized with the input command.

In this way, the user may set an X-ray irradiation condition whilechecking a portion of an object to be imaged from an image andintuitively recognize an X-ray irradiation condition that is currentlybeing set. For example, the user's workload may be reduced since movingthe input unit 160 such as a mouse (when selecting by clicking) ormoving the user's finger (when selecting by touch) decreases.

When setting an X-ray irradiation condition for all of the dividedregions is completed, the user may select the “exposure” button 151 l toperform X-ray imaging and may select the reset button 151 n whenattempting to initialize settings.

FIGS. 24 and 25 are views illustrating a screen that allows a user toselect an AEC sensor in the X-ray imaging apparatus according to anexemplary embodiment.

As described above, the plurality of AEC sensors 26 a, 26 b, and 26 cmay be used for automatically controlling a dose of X-rays. All or someof the plurality of AEC sensors 26 a, 26 b, and 26 c may be usedaccording to a portion to be imaged by X-rays. Thus, a selection of anAEC sensor may also be performed for each of a plurality of dividedregions.

A plurality of graphical objects respectively corresponding to theplurality of AEC sensors 26 a, 26 b, and 26 c may be displayed withinthe divided windows W1, W2, and W3, and the plurality of graphicalobjects may be implemented as buttons for receiving a selection by theuser.

The controller 140 may perform geometric registration of the cameraimage 152 by matching each point in the camera image 152 with a positionin the actual space. For example, the controller 140 may use therelationships between camera coordinate system, global coordinate systemand image coordinate system.

The controller 140 may acquire the positions of the AEC sensors 26 a, 26b, and 26 c that correspond to the position of the X-ray detector 200and coordinate the AEC sensors 26 a, 26 b, and 26 c with the cameraimage 152. The controller 140 may perform image processing whereby theAEC sensors 26 a, 26 b, and 26 c are coordinated with the camera image152 and the graphical objects that correspond to the AEC sensors aresuperimposed onto the camera image 152.

As illustrated in FIG. 24, a plurality of AEC sensor buttons 153 a-1,153 b-1, and 153 c-1, a plurality of AEC sensor buttons 153 a-2, 153b-2, and 153 c-2, and a plurality of AEC sensor buttons 153 a-3, 153b-3, and 153 c-3 respectively corresponding to the plurality of AECsensors 26 a, 26 b, and 26 c may be displayed. Each of the AEC sensorbuttons may be displayed at a position corresponding to its AEC sensor.

The user may select an AEC sensor to be used for each of the pluralityof divided regions. When a button corresponding to an AEC sensor to beused among the plurality of AEC sensor buttons 153 a-1, 153 b-1, and 153c-1 in the first divided window W1 is selected, the settings window 151interoperates therewith, and the selection is reflected and displayedalso on the AEC selection button 151 g on the settings window 151.

Conversely, when a selection of an AEC sensor is input using the AECselection button 151 g on the settings window 151 as illustrated in FIG.25, the camera image 152 interoperates therewith, and the selection isreflected and displayed also on the plurality of AEC sensor buttons 153a-2, 153 b-2, and 153 c-2.

When the selection of an AEC sensor is input, an AEC sensor buttoncorresponding to the selected AEC sensor may be highlighted by a changein color thereof, darkening or lightening an edge thereof, flickering ofthe edge thereof, etc. to reflect that the corresponding AEC sensor hasbeen selected. Alternatively, the selected AEC sensor and non-selectedAEC sensor may be distinguished from each other by solid line and dottedline. Alternatively, on/off may be displayed as text on the AEC sensorbuttons, and when an AEC sensor button with on is selected, the text maychange from on to off. When an AEC sensor button with off is selected,the text may change from off to on.

For example, when a check box above the AEC selection button 151 g isselected, the plurality of AEC sensors may be turned on or off.

The selected AEC sensor may be turned on when an X-ray imaging isperformed, and the non-selected AEC sensor may be turned off when anX-ray imaging is performed. However, the reverse may be possible.

Alternatively, an AEC sensor may also be automatically selected by thecontroller 140 based on a size of each of the plurality of dividedregions. For example, the controller 140 may exclude AEC sensors thatare disposed outside the X-ray irradiation region from being selected.

For example, the controller 140 may detect a contour or edge of theobject 1 in the camera image 152 via image processing such as contourdetection or edge detection and turn off the AEC sensor outside theobject 1.

If the AEC sensor outside the object 1 is not turned off, the AEC sensormay directly receive X-rays that have not passed through the object 1.This causes the amount of X-rays received by the AEC sensor to quicklyexceed a predetermined amount. In this case, the quality of an X-rayimage may be degraded due to the lack of X-ray dose irradiated on theobject 1.

Thus, the controller 140 may prevent degradation in quality of an X-rayimage by turning off an AEC sensor that is positioned outside the object1.

Even when the controller 140 has selected an AEC sensor, the controller140 may display which AEC sensor has been selected on the display 150.That is, the selection by the controller 140 may also be reflected inthe plurality of AEC sensor buttons 153 a-2, 153 b-2, and 153 c-2 andthe AEC selection button 151 g on the settings window 151.

As described above, when the AEC sensor button displayed on the cameraimage 152 and the AEC selection button 151 g on the settings window 151interoperate with each other, the user may more intuitively recognize aposition of the AEC sensor selected by the user.

For example, since the X-ray detector 200 is blocked by the object 1during X-ray imaging, the user is not able to directly recognize aposition of the AEC sensors. According to the exemplary embodimentdescribed above, the display 150 may display the AEC sensor buttons overthe camera image 152, thereby enabling the user to intuitively andconveniently recognize a relationship between positions of an actualobject and AEC sensors.

When setting an X-ray irradiation condition for each of the dividedregions is completed and the exposure button 151 l is selected, theX-ray imaging apparatus 100 may automatically control positions of theX-ray source 110 and the X-ray detector 200 and perform stitchingimaging. Hereinafter, this will be described with reference to FIGS. 26Ato 26C.

FIGS. 26A to 26C are views related to a case in which stitching imagingis performed by controlling a tilt angle of the X-ray source in theX-ray imaging apparatus according to an exemplary embodiment. In anexemplary embodiment, a case in which imaging is performed by mountingthe X-ray detector 200 on the stand 20 is given as an example.

Before operating the X-ray imaging apparatus 100, calibration may beperformed to calculate a location relationship between a camera imageobtained through imaging device 120 and an X-ray image.

For example, when the stitching region S is divided into the threeregions S₁, S₂, and S₃, the controller 140 calculates a first locationor a first tilt angle at which the first divided region S₁ is irradiatedwith X-rays, a second location or a second tilt angle at which thesecond divided region S₂ is irradiated with X-rays, and a third locationor a third tilt angle at which the third divided region S₃ is irradiatedwith X-rays, based on the previous calibration result.

Prior to performing stitching imaging, it may be assumed that the X-raysource 110 has been moved to a position corresponding to the X-raydetector 200. For example, when both the stand 20 and the table 10 arepresent in an examination room, and the user has selected the stand 20using the capture position setting button 151 d, the X-ray source 110may be automatically moved to a position corresponding to the stand 20.The position of the X-ray source 110 corresponding to the stand 20 maybe pre-stored.

Alternatively, the X-ray source 110 may also be manually moved by theuser to the position corresponding to the stand 20.

For example, when the stitching region S is divided into three regionsS₁, S₂, and S₃, the tilt angle of the X-ray source 110 may be adjustedto an angle corresponding to the first divided region S₁ as illustratedin FIG. 26A to capture a first divided X-ray image, the tilt angle ofthe X-ray source 110 may be adjusted to an angle corresponding to thesecond divided region S₂ as illustrated in FIG. 26B to capture a seconddivided X-ray image, and the tilt angle of the X-ray source 110 may beadjusted to an angle corresponding to the third divided region S₃ asillustrated in FIG. 26C to capture the third divided X-ray image. Here,the height of the X-ray source 110 from the ground may be fixed.

The controller 140 may transmit a control signal to a motor that adjuststhe tilt angle of the X-ray source 110 to adjust the tilt angle of theX-ray source 110 to an angle corresponding to each of the dividedregions.

For example, when X-ray irradiation conditions of the first dividedregion, the second divided region, and the third divided region are setto be different from each other, the X-ray source 110 or the X-raydetector 200 may be controlled to correspond to a set irradiationcondition when each of the divided regions is being captured.

In another example, the height of the X-ray source 110 may also beadjusted to a height corresponding to the first divided region S₁ tocapture the first divided X-ray image, adjusted to a heightcorresponding to the second divided region S₂ to capture the seconddivided X-ray image, and adjusted to a height corresponding to the thirddivided region S₃ to capture the third divided X-ray image. Here, thetilt angle of the X-ray source 110 may be fixed.

In yet another example, the height and the tilt angle of the X-raysource 110 may also be simultaneously adjusted.

In both of the examples, the X-ray detector 200 is moved to a positioncorresponding to each of the divided regions. To move the X-ray detector200, the mounting unit 24 on which the X-ray detector 200 is mounted maybe moved in the vertical direction. The controller 140 may transmit acontrol signal to a motor driving the mounting unit 24 to move the X-raydetector 200 mounted on the mounting unit 24 to a position correspondingto each of the divided regions.

When each of the divided regions is designated, the controller 140 maycalculate an actual position of the X-ray detector 200 to match thecenter of the designated divided region and the center of the X-raydetector 200. Also, as described regarding FIGS. 11-15, aligning theX-ray source 110 and the X-ray detector 200 may be performed.

The controller 140 may generate the divided X-ray images X₁, X₂, and X₃respectively corresponding to the divided regions S₁, S₂, and S₃ afterprocessing electrical signals due to detection, by the X-ray detector200, of X-rays that have passed through the object and may stitch thedivided X-ray images X₁, X₂, and X₃ to generate one stitched-togetherimage X₁₂₃.

The display 150 may display the generated stitched-together image or mayalso display the divided X-ray images.

For example, the controller 140 may combine electrical signals outputfrom the X-ray detector 200 to generate an X-ray image or performvarious types of image processing of the generated X-ray image. Thecontroller 140 may use a high pass filter to add a sharpening effect tothe whole image or a part of the image or may use a low pass filter toadd a blurring effect to the whole image or a part of the image.

To perform the image processing described above, the controller 140 mayinclude a graphics processing unit (GPU).

Hereinafter, a method for controlling an X-ray imaging apparatusaccording to an exemplary embodiment will be described.

The X-ray imaging apparatus 100 described above may be used in themethod for controlling an X-ray imaging apparatus according to anexemplary embodiment. Consequently, the descriptions given above withreference to FIGS. 1 to 26C may also be identically applied to themethod for controlling an X-ray imaging apparatus.

FIG. 27 is a flowchart related to a method for controlling an X-rayimaging apparatus according to an exemplary embodiment.

Referring to FIG. 27, the imaging device 120 is used to capture a cameraimage (operation 301). An object may be disposed in front of the X-raydetector 200 that will be used in X-ray imaging, and the X-ray detector200 may be mounted on the stand 20 or the table 10 or may also beportably used. The camera image may be a video or a still image capturedat predetermined intervals.

The display 150 displays graphical objects displaying various types ofinformation together with the camera image (operation 302). Thegraphical objects may include size displaying graphical objects 152 eand 152 f showing a size of the collimation region, a length displayinggraphical object 152 g showing the length of the object, and a distancedisplaying graphical object 152 h showing an SID or SOD.

The description related to a method for displaying each of the graphicalobjects is the same as in the exemplary embodiment of the X-ray imagingapparatus 100 described above.

The irradiation window W may be displayed by being overlaid on thecamera image 152 to display the size displaying graphical objects 152 eand 152 f, and the size displaying graphical objects 152 e and 152 f maybe displayed at an upper end portion and a side portion of theirradiation window W to show a width and height of the collimationregion.

The user may adjust the size of the irradiation window W with referenceto the displayed size displaying graphical objects 152 e and 152 f toadjust the size of the collimation region and may adjust the stitchingregion with reference to the length displaying graphical object 152 g(operation 303). Alternatively, the user may adjust the distance betweenthe X-ray source 110 and the X-ray detector 200 with reference to thedistance displaying graphical object 152 h, input or change varioustypes of settings, input an exposure command to begin X-ray imaging, orinput a cancel command for setting or an operation.

According to this example, setting by the user may be guided by thedisplaying the graphical objects showing the size of the collimationregion, the length of the object, and information on the SOD or the SID.For example, when a captured X-ray image does not include the wholeportion desired to be imaged and thus imaging needs to be performedagain, the size displaying graphical objects 152 e and 152 f or thelength displaying graphical object 152 h may be displayed to guide theuser on how much the size of the collimation region or the stitchingregion has to be increased.

When all required settings are determined and an X-ray exposure commandis input, the adjusted collimation region or stitching region isirradiated with X-rays (operation 304).

The X-ray detector 200 receives X-rays that have passed through theobject 1 and stores and outputs electrical signals corresponding to thereceived X-rays. The controller 140 may acquire an X-ray image based onthe output electrical signal (operation 305), and the acquired X-rayimage may be provided to the user through the display 150 provided atthe work station 180 or the sub-display device 80.

FIG. 28 is a flowchart related to an example of performing dividedimaging in the method for controlling an X-ray imaging apparatusaccording to an exemplary embodiment.

Referring to FIG. 28, the imaging device 120 is used to capture a cameraimage (operation 310). The object may be disposed in front of an X-raydetector to be used in X-ray imaging, and the X-ray detector may bemounted on the stand 20 or the table 10.

The captured camera image is displayed on the display 150 (operation311). The camera image 152 may be displayed on the display 150 in realtime. The display 150 may be the display 182 provided at the workstation 180 or may also be the sub-display 81 included in thesub-display device 80 mounted on the X-ray source 110. Alternatively,the display 150 may also be a display provided at a mobile device suchas a smartphone or a tablet PC.

A designation related to a stitching region is received from the user(operation 312). As it has been described in the exemplary embodiment ofthe X-ray imaging apparatus 100 described above, the user may designatea start point and an end point of the stitching region on the cameraimage. For example, the start point of the stitching region may bedesignated using the top line L_(T), and the end point of the stitchingregion may be designated using the bottom line L_(B). Meanwhile, aposition of the stitching region may also be designated according to aselected imaging protocol instead of being directly designated by theuser. For example, when a protocol related to imaging a chest isselected, a stitching region including the chest may be automaticallydesignated.

When the stitching region is designated, the stitching region S may bedivided (operation 313). For example, the controller 140 may divide thestitching region S into a plurality of divided regions having the samesize through uniform division. A size of one divided region is notlarger than a size of a detection region of the X-ray detector 200.Here, the size of a divided region signifies a size in the verticaldirection based on the ground. In another example, the stitching regionS may also be divided so that the divided regions thereof have differentsizes and may also be divided by the user directly designating aposition and shape of each of the divided regions instead of beingautomatically divided by the controller 140. In an example in which thestitching region S is directly divided by the user, the boundary linesforming the divided windows W1, W2, and W3 displayed by being overlaidon the camera image 152 of the display 150 may be moved to adjust aposition and size of each of the divided windows.

An X-ray irradiation condition is set for each of the divided regions(operation 314). Setting the X-ray irradiation condition may beperformed by the user's input. As it has been described in the exemplaryembodiment of the X-ray imaging apparatus 100 above, the display 150 maydisplay the divided windows W1, W2, and W3 respectively corresponding tothe divided regions on the camera image 152 and may display the settingswindow 151 for setting an X-ray irradiation condition for each of thedivided regions together. A GUI through which an X-ray irradiationcondition may be set for each of the divided regions may be displayed onthe settings window 151, and the GUI may be formed of a plurality ofgraphical objects each having a specific function. The settings window151 and the divided windows W1, W2, and W3 may interoperate with eachother such that, when a divided region is selected within the settingswindow 151, a divided window corresponding to the selected dividedregion is highlighted and displayed, and, when a divided region isselected using a divided window, a settings menu corresponding to theselected divided region may be activated. For example, the settingbutton 152 d for receiving a setting of X-ray irradiation conditionssuch as a tube voltage, a tube current, and an X-ray exposure time maybe displayed together with the divided windows W1, W2, and W3, andsettings input through the setting button 152 d and a numerical valuedisplayed on the settings window 151 may be synchronized with eachother.

For example, identification tags displayed to distinguish a dividedregion currently targeted for setting an X-ray irradiation condition onthe settings window 151 may be matched with the identification tags 152c-1, 152 c-2, and 152 c-3 displayed on the divided windows W1, W2, andW3.

In this way, the user may accurately recognize a position at which adivided region whose X-ray irradiation condition is currently being setis disposed, and this allows an X-ray irradiation condition to beaccurately set for each of the divided regions.

FIG. 29 is a flowchart illustrating an example of performing stitchingimaging by controlling an X-ray irradiation condition to be differentfor every divided region in the method for controlling an X-ray imagingapparatus according to an exemplary embodiment.

Referring to FIG. 29, an X-ray source is controlled according to anX-ray irradiation condition set for a first divided region (operation320). The X-ray irradiation condition may include a tube voltage, a tubecurrent, and an exposure time and may further include other conditionssuch as an AEC sensor, sensitivity, density, grid, and filter as in theexample described above. For example, the X-ray detector 200 may also becontrolled according to the type of the X-ray irradiation condition.

The X-ray source and the X-ray detector are controlled to have aposition or angle corresponding to the first divided region (operation321). Since the X-ray detector 200 may move in a direction in which astitching region is divided, the controller 140 may control the mountingunits 14 and 24 on which the X-ray detector 200 is mounted to control aposition of the X-ray detector 200. The X-ray source 110 may be moved inthe direction in which the stitching region is divided while a tiltangle thereof is fixed, and the tilt angle may be controlled tocorrespond to the first divided region while the height of the X-raysource 110 from the ground is fixed.

When the X-ray source 110 and the X-ray detector 200 are controlled tobe disposed at positions corresponding to the first divided region,X-rays are radiated to perform X-ray imaging of the first divided region(operation 322). When the X-ray imaging of the first divided region isperformed, a first divided X-ray image is acquired.

The X-ray source is controlled according to an X-ray irradiationcondition set for a second divided region (operation 323). The X-rayirradiation condition set for the second divided region may be differentfrom or the same as that set for the first divided region.

The X-ray source and the X-ray detector are controlled to have aposition or angle corresponding to the second divided region (operation324). The X-ray detector 200 may move in the direction in which thestitching region is divided. The X-ray source 110 may be moved in thedirection in which the stitching region is divided while a tilt anglethereof is fixed, and the tilt angle may be controlled to correspond tothe second divided region while the height of the X-ray source 110 fromthe ground is fixed.

When the X-ray source 110 and the X-ray detector 200 are controlled tobe disposed at positions corresponding to the second divided region,X-rays are radiated to perform X-ray imaging of the second dividedregion (operation 325). When the X-ray imaging of the second dividedregion is performed, a second divided X-ray image is acquired.

When the stitching region includes three or more divided regions,divided imaging up to a third divided region or a fourth divided regionmay also be performed like the process described above. For example,when the stitching region includes three divided regions, the X-raysource may be controlled according to an X-ray irradiation condition setfor the third divided region. The X-ray irradiation condition set forthe third divided region may be the same as or different from that setfor the first divided region or the second divided region. When theX-ray source and the X-ray detector are controlled to have a position orangle corresponding to the third divided region, and the X-ray source110 and the X-ray detector 200 are controlled to be disposed atpositions corresponding to the third divided region, X-rays areirradiated to perform X-ray imaging of the third divided region. Whenthe X-ray imaging of the third divided region is performed, a thirddivided X-ray image is acquired. When the stitching imaging iscompleted, the acquired divided X-ray images are stitched to generateone stitched-together image (operation 326). The generatedstitched-together image may be displayed on the display 150.

Although it has been described in the above embodiment that positions ofthe X-ray source and the X-ray detector are controlled after controllingbased on the X-ray irradiation condition is performed, an order ofcontrolling may change, or the controlling based on the X-rayirradiation condition and the controlling of the position may also besimultaneously performed.

Some of the operations of the X-ray imaging apparatus and the method forcontrolling the same described above may be stored as programs in acomputer-readable recording medium. The recording medium may be amagnetic recording medium such as a read-only memory (ROM), a floppydisk, and a hard disk, or an optical recording medium such as a compactdisk (CD)-ROM and a digital versatile disk (DVD). However, types of therecording medium are not limited to the examples above.

The recording medium may be included in a server that providesapplications or programs, and a work station, a sub-display device, or amobile device may access the server via a communication protocol such asthe internet to download a corresponding program.

For example, when the display 150 and the input unit 160 described aboveare included in a mobile device, the screen described above may bedisplayed on the display 150 after the mobile device downloads,installs, and executes a program.

Steps of executing some of the operations of the controller 140described above may be included in the program. In this case, the mobiledevice may generate a control command and transmit the control commandto the X-ray imaging apparatus 100.

Alternatively, the mobile device may transmit information related to acontrol command input by the user to the X-ray imaging apparatus 100,and the controller 140 may control the X-ray imaging apparatus 100according to the control command input by the user.

According to an X-ray imaging apparatus and a method for controlling thesame according to an aspect, a plurality of divided regions in whichstitching imaging will be performed is displayed in a camera image, andthe divided regions displayed on the camera image interoperate with anX-ray irradiation condition setting screen for each of the dividedregions to allow a user to intuitively and easily recognize the dividedregion for which an X-ray irradiation condition is being set.

The foregoing exemplary embodiments and advantages are merely exemplaryand are not to be construed as limiting. The present teaching can bereadily applied to other types of apparatuses. Also, the description ofthe exemplary embodiments is intended to be illustrative, and not tolimit the scope of the claims, and many alternatives, modifications, andvariations will be apparent to those skilled in the art.

What is claimed is:
 1. An X-ray imaging apparatus comprising: an imagingdevice configured to capture a camera image of a target; a controllerconfigured to stitch a plurality of X-ray images of respective dividedregions of the target to generate one X-ray image of the target; and adisplay configured to display a settings window that provides agraphical user interface (GUI) for receiving a setting of an X-rayirradiation condition for the respective divided regions, and displaythe camera image in which positions of the respective divided regionsare displayed.
 2. The X-ray imaging apparatus of claim 1, wherein thedisplay is configured to display windows that show the positions of therespective divided regions by overlaying the windows on the cameraimage.
 3. The X-ray imaging apparatus of claim 2, wherein the display isconfigured to display the settings window and the camera image on whichthe windows are overlaid to be interoperative with the settings window.4. The X-ray imaging apparatus of claim 3, wherein, in response to oneof the respective divided regions being selected, the display isconfigured to activate the GUI for receiving a setting of the X-rayirradiation condition for the selected divided region, display the GUIon the settings window, and display the position of the selected dividedregion on the camera image.
 5. The X-ray imaging apparatus of claim 3,wherein the display is configured to display identification tagscorresponding to the respective divided regions on the settings window,and, in response to one of the identification tags being selected,activate the GUI for receiving a setting of the X-ray irradiationcondition for the respective divided region corresponding to the one ofthe identification tags which has been selected.
 6. The X-ray imagingapparatus of claim 5, wherein the display is configured to display, onthe camera image, the position of the respective divided regioncorresponding to the one of the identification tags that has beenselected on the settings window.
 7. The X-ray imaging apparatus of claim3, wherein, in response to one of the windows displayed on the cameraimage being selected, the display is configured to activate the GUI forreceiving a setting of the X-ray irradiation condition of the respectivedivided region corresponding to the one of the windows which has beenselected.
 8. The X-ray imaging apparatus of claim 3, wherein the displayis configured to display a graphical object for receiving the setting ofthe X-ray irradiation condition by overlaying the graphical object onthe camera image, and display the GUI on the settings window bysynchronizing the GUI with a command input via the graphical objectdisplayed on the camera image.
 9. The X-ray imaging apparatus of claim5, wherein the display is configured to display, on the windowsdisplayed on the camera image, a set of identification tags eachrespectively matching the identification tags displayed on the settingswindow.
 10. The X-ray imaging apparatus of claim 1, wherein the displayis configured to display a top line showing a top boundary of an entirestitching region, which includes the respective divided regions, and abottom line showing a bottom boundary of the stitching region, on thecamera image.
 11. The X-ray imaging apparatus of claim 10, wherein thedisplay is configured to display the top line and the bottom line atpositions corresponding to a selected protocol for an X-ray imaging ofthe target.
 12. The X-ray imaging apparatus of claim 10, wherein thedisplay is configured to display the bottom line at a lower end portionof the camera image.
 13. A method for controlling an X-ray imagingapparatus, the method comprising: capturing a camera image of a target;receiving a selection related to a stitching region including dividedregions, via the camera image; and displaying a settings window, whichprovides a graphical user interface (GUI) for receiving a setting ofX-ray irradiation conditions for the divided regions, and the cameraimage in which positions of the divided regions are displayed.
 14. Themethod of claim 19, wherein the displaying includes: displayingpositions of the divided regions by overlaying graphical windows on thecamera image.